GNU gperf

GNU gperf is a program that generates perfect hash
functions for sets of keywords. A perfect hash
function is a hash function and a data structure
that allows recognition of a key word in a set of
words using exactly 1 probe into the data
structure. Output from the GPERF program is used
to recognize reserved words in the GNU C, GNU
C++, and GNU Pascal compilers, as well as with the
GNU indent program.

Release Notes: This release produces smaller lookup tables, is much faster, and doesn't need guesswork from the user. Most options can now be specified in the input file rather than on the command line. Additional options allow generation of optimized code for use in shared libraries.